The present invention relates to a railroad system and, in particular, to a railroad system that utilizes multiple tracks.
The railroad industry has a long history of being one of the most cost-effective means to transport goods across landmasses. Most railroad systems employ two sets of parallel railroad tracks. Each set of tracks consists of a pair of parallel rails that are set apart at a fixed distance of approximately five feet. The rails in a set are connected to one another by railroad ties, which are typically rectangular lengths of treated wood placed beneath the rails and transverse thereto. The rails are affixed to the ties using steel spikes. The two sets of tracks are laid parallel to one another at approximately the same elevation so that the inner rails of each set are at a distance of approximately 8½ feet from one another.
The tracks are typically utilized by trains, wherein one set of tracks is used for trains traveling in one direction and the other set of rails is used for trains traveling in the opposite direction. Trains typically consist of one or more powered engines coupled together at the front of the train pulling a multiplicity of cars, which may include box cars, tanker cars, flatbed cars, bin cars, passenger cars, etc., that are aligned in a single row and coupled together. Each car rides on a set of car-trucks that include a plurality of wheels riding on and rolling along one of the sets of tracks.
Such trains can carry a significant load of cargo; however, it would be possible to carry even more cargo in a more cost-effective manner if a multiple track railroad system were employed having trains that span and utilize both sets of tracks. Of course, specific technical features (such as a means to compensate for adjustment in the distance or heights between the sets of parallel tracks) not required on trains that run on a single set of tracks will be required for trains that run on both sets of tracks.
U.S. Pat. No. 722,436 to Suppan et al. discloses a truck for transport of ships. The truck disclosed by Suppan is supported on and runs on pairs of wheels running on two sets of parallel tracks.
U.S. Pat. No. 772,482 to Thomson discloses a tank for carrying a boat. The tank is supported by wheels running on a rail track. The embodiment depicted shows the rail tracks having four longitudinal rails and a central rail standing higher than the other rails and adapted to guide the tank and wheel frames transversely.
U.S. Pat. No. 1,392,523 to Pereire et al. discloses a large capacity railway carriage mounted on a plurality of bogie trucks and designed to travel on a plurality of railroad tracks. In one embodiment, eight bogie trucks are used with four bogie trucks on each of two sets of tracks.
U.S. Pat. No. 1,634,490 to Collis discloses a railway train with cars of such width that two lines of track are required for their support (i.e., lines of tracks with two rails each where normally one line is for a train traveling in one direction and the other line is for a train traveling in the opposite direction). The car disclosed by Collis has a width of twenty-one feet and four inches, instead of the customary eight feet and nine inches. For passengers, the car includes six longitudinal rows of seats instead of the customary two rows of seats.
U.S. Pat. No. 2,234,522 to Fleet et al. discloses a rail car spanning two sets of tracks for carrying and launching an airplane. Several embodiments are discussed by Fleet et al. for the purpose of accommodating deviations in the distance between the tracks. One embodiment includes a connecting rod and lever arm connecting tension links in side-by-side rail trucks. In another embodiment, the tracks are connected by a pair of connecting rods pivotally connected to a compensating lever.
U.S. Pat. No. 2,246,716 to Bottrill discloses a mobile landing platform for an airplane. The landing platform is supported by two automotive railway cars that are attached and secured to one another with cross beams so that the cars are side by side on a double-track railroad.
U.S. Pat. No. 3,902,433 to Borchert et al. discloses a large volume railway car for movement on a four-rail track in which each end of the railway car is provided with two substantially parallel interconnected bogies having two or more axles. The bogie pairs are interconnected to one another by a common bridge. The wheel sets of the bogies have wheel rims arranged on the outer sides of each pair of tracks on which the bogie is riding to keep the bogies on the track rails.
U.S. Pat. No. 5,295,442 to Carpenter discloses a multiple track railroad system having a greater than standard width to span adjacent parallel tracks. The railroad track system in Carpenter is designed to ride on standard wheel trucks on each of the parallel tracks. Carpenter discloses laterally spaced apart and coupled conventional engines to pull the cars, and an interconnection between the laterally spaced locomotives is provided to enable the train to be operated by a single crew in the cab of one locomotive. Carpenter also discloses a single locomotive spanning two adjacent parallel tracks, and couplings are provided to enable conventional cars to be coupled to wider cars.
U.S. Pat. No. 5,802,981 to Kassab discloses a railway vehicle having 12 wheel and axle assemblies grouped into six two-axle assemblies. Three truck assemblies are mounted on each of two span bolsters, which in turn are mounted on opposite ends of the railway vehicle. The truck assemblies are rotatably mounted to the span bolster and the span bolster is rotatably mounted to the railway vehicle.